Re: assimilation, the Borg didn't
assimilate people at first. They weren't interested in people at all, only their technology. That was another thing that made them scary. The just didn't give a crap about you. You could study them, shoot at them, beam over to their ship, but they didn't care, because you were little more than an insect.
An enemy that is completely indifferent to your suffering is far more frightening than an enemy who passionately hates you.